Indeed it was. A dark, grungy sci-fi film that would make Carpenter proud, "Snowpiercer" is a bizarre, visually interesting movie about a train that carries the last surviving members of humanity as it circles the frozen globe (you see, humans, in trying to fight global warming, came up with a way to combat greenhouse gases; it worked so well the planet became too frozen to support life).

Aboard the train: Chris Evans, Jamie Bell, John Hurt, Tilda Swinton, Octavia Spencer, Ed Harris and Bong Joon-ho regulars from his Korean films, Song Kang-ho and Ko Ah-sung. The idea: Evans leads a group of squalid individuals from the back of the train on a revolt to push to the front of the train, where the more well-to-do people live.

Class warfare is something deep within Bong's work (he majored in sociology, not film), which includes the great "Memories of Murder" (2003), about serial killings in the 1980s, the monster movie "The Host" (2006) and the sociological drama "Mother" (2009).

"It shows us who we are as people," Bong said through a translator during a recent stop in San Francisco. "In desperate moments, you can see who people are, what they're made of, especially in a genre like sci-fi, where you can really express that.

"I'm criticizing a system that doesn't help the weak people. ... I'm not sure if it's possible, but if class differences disappear, that would be a good world to live in."

The film is based on a French graphic novel, "Le transperceneige," and filmed on a claustrophobic, rolling set in Prague. To keep the cast loose, Bong, allowed actors to help craft their own characters (Swinton added a Yorkshire accent to her shrill villain). He was especially giving to Evans, who would like to transition from his "Captain America" roles to directing.

Evans frequently asked questions during the shoot - he was, in fact, preparing to direct his first film, "1:30 Train," which is now in post-production.

"We wanted each other, in a way," Bong said. "Between his Marvel films and playing Captain America, Chris actively sought more serious and character-driven films, like the drug-addicted lawyer in 'Puncture.' When we were casting 'Snowpiercer,' Chris heard about it and asked to be in it, and I felt I really needed someone like Chris. ... He had a lot of suggestions for the script and his character."

To achieve the unique production design - which looks more like steampunk anime than sci-fi - Bong hired a designer, Czech-born Ondrej Nekvasil ("The Illusionist"), who had never done a science fiction film before.

"The whole story relies on the production design," Bong said. "That's one of the things that attracted me to the graphic novel, the possibilities of production design. One of the things I liked about Ondrej was that he hadn't done sci-fi before. I wanted to avoid the cliched sci-fi design."

Well, heck, what child of the movies wouldn't want to play with his very own train set? It occurs to Bong that he is making the kind of films that inspired him as a child.

Which brings us to Hurt. One of Bong's scariest memories as a kid watching movies was that classic scene in Ridley Scott's "Alien" (1979) when the creature first bursts out of Hurt's stomach. One can imagine Bong casting Hurt just so he could chat about that scene.

"He's a living legend," Bong laughed. "I couldn't not ask about that. I asked him about how Ridley Scott shot that. I asked about how David Lynch shot 'Elephant Man.' We're supposed to be working, but I kept asking him about his career. Fortunately, John's a good guy and was happy to talk about his experiences."